.TH std::return_temporary_buffer 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::return_temporary_buffer \- std::return_temporary_buffer

.SH Synopsis
   Defined in header <memory>
   template< class T >                    (deprecated in C++17)
   void return_temporary_buffer( T* p );  (removed in C++20)

   Deallocates the storage referenced by p.

   If p is not a pointer value returned by an earlier call to
   std::get_temporary_buffer, or has been invalidated by an intervening
   std::return_temporary_buffer call, the behavior is undefined.

.SH Parameters

   p - the pointer referring to the storage to be declloated

.SH Return value

   \fI(none)\fP

.SH Exceptions

   Throws nothing.

.SH Example



// Run this code

 #include <algorithm>
 #include <iostream>
 #include <iterator>
 #include <memory>
 #include <string>

 int main()
 {
     const std::string s[] = {"string", "1", "test", "..."};
     const auto p = std::get_temporary_buffer<std::string>(4);
     // requires that p.first is passed to return_temporary_buffer
     // (beware of early exit points and exceptions), or better use:
     std::unique_ptr<std::string, void(*)(std::string*)> on_exit(p.first,
     [](std::string* p)
     {
         std::cout << "returning temporary buffer...\\n";
         std::return_temporary_buffer(p);
     });

     std::copy(s, s + p.second,
               std::raw_storage_iterator<std::string*, std::string>(p.first));
     // has same effect as: std::uninitialized_copy(s, s + p.second, p.first);
     // requires that each string in p is individually destroyed
     // (beware of early exit points and exceptions)

     std::copy(p.first, p.first + p.second,
               std::ostream_iterator<std::string>{std::cout, "\\n"});

     std::for_each(p.first, p.first + p.second, [](std::string& e)
     {
         e.~basic_string<char>();
     }); // same as: std::destroy(p.first, p.first + p.second);

     // manually reclaim memory if unique_ptr-like technique is not used:
     // std::return_temporary_buffer(p.first);
 }

.SH Output:

 string
 1
 test
 ...
 returning temporary buffer...

   Defect reports

   The following behavior-changing defect reports were applied retroactively to
   previously published C++ standards.

      DR    Applied to             Behavior as published              Correct behavior
                       the storage allocated by                       the behavior is
   LWG 2072 C++98      std::get_temporary_buffer                      undefined in this
                       could be deallocated multiple times            case

.SH See also

   get_temporary_buffer  obtains uninitialized storage
   (deprecated in C++17) \fI(function template)\fP
   (removed in C++20)
